.\"
.Dd January 30, 2020
.Dt LOGIN.ACCESS 5
.Os
.Sh NAME
.Nm login.access
.Nd login access control table
.Sh SYNOPSIS
.Pa /etc/login.access
.Sh DESCRIPTION
The
.Nm
file specifies (user, host) combinations and/or (user, tty)
combinations for which a login will be either accepted or refused.
.Pp
When someone logs in, the
.Nm
is scanned for the first entry that
matches the (user, host) combination, or, in case of non-networked
logins, the first entry that matches the (user, tty) combination.
The
permissions field of that table entry determines whether the login will
be accepted or refused.
.Pp
Each line of the login access control table has three fields separated by a
.Ql \&:
character:
.Ar permission : Ns Ar users : Ns Ar origins
.Pp
The first field should be a "+" (access granted) or "-" (access denied)
character.
.Pp
The second field should be a list of one or more login names,
group names, or ALL (always matches).
Group names must be enclosed in
parentheses if the pam module specification for
.Pa pam_login_access
specifies the
.Pa nodefgroup
option.
Otherwise, group names will only match if no usernames match.
.Pp
The third field should be a list
of one or more tty names (for non-networked logins), host names, domain
names (begin with "."), host addresses, internet network numbers (end
with "."), ALL (always matches) or LOCAL (matches any string that does
not contain a "." character).
If you run NIS you can use @netgroupname
in host or user patterns.
.Pp
The EXCEPT operator makes it possible to write very compact rules.
.Pp
The group file is searched only when a name does not match that of the
logged-in user.
Only groups are matched in which users are explicitly
listed: the program does not look at a user's primary group id value.
.Sh FILES
.Bl -tag -width /etc/login.access -compact
.It Pa /etc/login.access
login access control table
.El
.Sh SEE ALSO
.Xr login 1 ,
.Xr pam_login_access 8
.Sh AUTHORS
.An Guido van Rooij
